KaShDa 2" - 12" Silver Plated Double 15MM Flat Lobster Claw Chain/Necklace Extender 15MM (1/2") Silver plated diamond embossed flat lobster claws. 3.7MM Silver Plated Brass Core Curb Chain. Easy to move from one piece of jewelry to another. Use on chains or necklaces. Use with your chunky necklaces, these are strong enough to hold jewelry pieces weighing up to 15 ounces. The olny difference between the lengths is the length of the chain.